How strong are liner locks and frame locks?

[Folderguy]

While there are tests done by Cold Steel showing how strong their TriAd locks are on the various models that have them, I've not seen comparative videos on the strength of various liner locks and frame locks.

On most knives, the strength of the lock may not be an issue, especially if the knife is only used as intended, for the lock won't usually come into any serious stress, but on knives that are put forth as hard use knives, or combat knives, the strength of the lock can be a more important one.

I'm thinking specifically of knives that may be used for self defense in which a powerful thrust may be employed. Obviously, if the blade hits something really hard at certain angles, the lock will be put under tremendous stress, and if the blade folds on the fingers, serious injury can be the result.

On certain designs, for instance on this ZT 0200,

if the liner lock, which is pretty beefy, were to fail, because of the design of the choil and the flipper, it appears that the flipper would really pinch one's forefinger (if in the saber grip) and thus hopefully spare one's fingers. Or do I have that wrong?

If you have any experience with this subject, I'm all ears.

Thanks,
Folderguy

 

[thegeek574]

You have the idea correct. It all depends on the knife. If you can make a ZT 0200 fail, you either got a faulty unit or you were doing something the knife was not intended to do. A knife does not have to be able to stab into a tree and survive. first of all, that tree never did anything to you, so you shouldn't be stabbing it. second of all, the only time that you should be stabbing is, unfortunately, into a person, and they are nowhere near as hard as a tree. Now, give me a no brand gas station knife and i bet i can make it fail in 30 seconds or less. It all depends on quality. The thing about a liner lock is that i would say that it's purpose is to keep the knife from closing back on your hand in the unlikely event that the blade gets pushed down. The triad lock completes that task effectively, as does the liner lock, frame lock, axis lock, hawk lock, and lock back, to name a few, when used properly. if you want something that can hold up to everything, do not get a prebroken knife.

 

[Joshua J.]

Word on the street is Liner Locks and Frame (Integral) Locks are about the same strength. Liner Locks are just harder to make correcly, so you have many more of those that will be unreliable.
I have used Kershaw's thick Liner lock, seen on the JYD 2 and ZT 0200, quite harshly. It held up admirably, and I trust it almost as much as the Spyderco Military (one of the only "technically correct" Liner Locks on the market).
That said, there is a chance that any knife produced is faulty and will fail. Therefore I treat every folder as though it will fail. Thus with knives that use a big flipper or finger choil I can be more free in the ways that I use them (while making sure to hold the knife correctly). When the lock fails the flipper or choil will hit my finger, on knives without I treat them with more caution, and tend to only use them for light cutting or kitchen duty.
I didn't start thinking about locks this way until abusing my Spyderco Chinook 3 to the point of failure. I did a lot of dumb things with it, but it has one of the strongest locks ever, so it's ok, right? On one of the spine whacks the blade closed, but the choil bounced off my finger. I was almost in shock that this knife with its super beefy lock, failed, and that I could have had a big cut on my finger. After that I was more adamant about the use of flippers and choils.

 

[hardheart]

liner and frame locks have roughly the same capability to handle a static load. They are lower on the totem pole for popular locks. Lockback, triad, compression, axis, and ball bearing are rated higher. There are many other locks as well, but I don't know where they sit. Vault, stud, ram, d.o.g., hawk, ti, arc, axial, matt, microbar, ultra, rolling, bolt action, tactical operation, viro, E, button, and plenty more